A plat is a map, prepared by a licensed land surveyor and approved by the local government, that legally creates lots in a subdivision and is recorded with the county. It shows each lot’s boundaries with dimensions and bearings, streets, easements, and notes that can affect what you can build. For homeowners, the recorded plat is often the best free source of lot dimensions and easements for a site plan or permit application.
Quick answer: A plat is a recorded map that creates and defines lots in a subdivision. It shows lot lines with bearings and distances, lot numbers, streets, easements, building lines and restrictive notes. Find yours through the county recorder or register of deeds using the subdivision name, book and page from your deed.
What a plat shows
| Element | Use for homeowners |
|---|---|
| Lot and block numbers | Identify your lot in legal descriptions |
| Bearings and distances | Lot dimensions for site plans |
| Curve data | Dimensions of curved lot lines |
| Lot areas | Lot size for coverage and FAR |
| Streets and right-of-way | Where public land begins |
| Easements | Utility, drainage and access strips |
| Building lines | Platted setbacks, sometimes stricter than zoning |
| Monuments | Physical corner markers |
| Notes and certifications | Restrictions, approvals, dedications |
For how plats are created when land is divided, see our pillar how to split a lot.
Plat vs survey vs site plan
| Document | Purpose | Prepared by |
|---|---|---|
| Plat | Legally creates lots; recorded | Licensed surveyor, approved by government |
| Boundary survey | Locates a lot’s boundaries and improvements on the ground | Licensed surveyor |
| Site plan | Shows existing and proposed work for a permit | Drafter, designer, owner or professional |
See site plan vs survey and types of land surveys.
How to find your plat
- Look at your deed or title policy for the legal description, such as “Lot 12, Block 3, Oak Hills Subdivision, Plat Book 45, Page 67”.
- Search the county recorder or register of deeds website for the plat book and page or subdivision name.
- Check the county GIS viewer, which sometimes links to plat images; see reading a GIS parcel map.
- Ask the planning office or recorder if you can’t find it online.
Lots described by metes and bounds, rather than lot and block, may not be on a subdivision plat; a survey is then the main source.
How to read a plat
- Find your lot by lot and block number.
- Read the lines: each has a bearing, such as N 45°30’00” E, and a distance in feet.
- Read curves from the curve table: radius, arc length, chord.
- Find easements: dashed lines with labels such as “10′ U.E.” (utility easement) or “D.E.” (drainage).
- Look for building lines: “25′ B.L.” means a platted building setback.
- Read the notes: restrictions on access, drainage, fences, floor elevations or use.
- Check the north arrow and scale.
Plat notes that affect building
Plat notes can impose rules beyond zoning: no direct driveway access to a main road, minimum finished floor elevations in flood-prone areas, drainage easements where fences are prohibited, tree preservation areas, or shared driveway arrangements. Reviewers check these, so read them before designing. See what is an easement.
Using a plat for your site plan
For many permits, a site plan drawn from the plat’s lot dimensions is accepted, especially where the work is comfortably within setbacks. Our site plans are often drafted from the recorded plat plus aerial imagery and your measurements, with the source noted. Where setbacks are tight or lines are uncertain, a survey is more reliable.
Limits of a plat
- It shows the design of the lots, not necessarily where monuments ended up on the ground.
- It doesn’t show houses, fences and improvements built later.
- Later replats or adjustments may have changed your lot.
- Older plats may have errors or lower precision.
Replats and amended plats
Lots can be changed after the original plat by replats, amended plats or lot line adjustments. Search the recorder for later documents referencing your subdivision to make sure you are using the current version.
Who prepares a plat
Only a licensed land surveyor can prepare a plat, and it must be approved by the local government before recording. Plats are often required to bear the surveyor’s seal and signatures of officials and owners. See our digital vs wet stamp guide for sealing rules.
Reading bearings and distances
Bearings describe a line’s direction as an angle from north or south toward east or west. “N 45°30’00” E” means start facing north and turn 45 degrees 30 minutes toward east. The distance after it, such as 120.00′, is the line’s length in feet. Going around your lot, each line has a bearing and distance, and together they close back to the starting corner. You don’t need to understand the maths to use a plat for a site plan; the distances give the lot’s shape, and the drafter uses the bearings to draw it accurately.
Common plat abbreviations
| Abbreviation | Meaning |
|---|---|
| U.E. | Utility easement |
| D.E. | Drainage easement |
| B.L. / B.S.L. | Building line / building setback line |
| R.O.W. | Right-of-way |
| I.P.F. / I.R.S. | Iron pipe found / iron rod set (corner monuments) |
| P.O.B. | Point of beginning |
| Δ, R, L, CH | Curve angle, radius, length, chord |
Plats and title
Title commitments list recorded plats and their restrictions as exceptions to coverage. Reading the plat alongside the title documents gives a full picture of easements and restrictions on your lot.
Frequently asked questions
What is a plat?
A recorded map that legally creates lots in a subdivision.
Where can I get a copy of my plat?
From the county recorder or register of deeds, often online.
Is a plat the same as a survey?
No. A plat creates lots; a survey locates boundaries and improvements for a specific lot.
Can I use my plat for a permit site plan?
Often, as the source of lot dimensions and easements, unless setbacks are tight.
What if my lot isn’t on a plat?
Lots described by metes and bounds may not be platted; a boundary survey is then the main source of dimensions.
What does B.L. mean on a plat?
Building line: a platted setback.
